Levels Of Thermal Insulation Research Articles

Estimating the compressive strength of lightweight foamed concrete using different machine learning-based symbolic regression techniques

The development of concrete with excellent water and frost resistance providing high level of sound and thermal insulation has triggered the formulation of foamed concrete. However, multiple laboratory studies are required to produce reasonable data to design the relevant codes and mathematics with which design of mixes is made easier at low cost. In this research paper, the artificial intelligence (AI)-based symbolic regression technique estimation of the compressive strength of foamed concrete has been reported. Foamed concrete has been a subject of serious research in sustainable built-environment due to its lightweight and structural functionality. In this research work, data gathering method was applied to gather a globally representative data base comprising concrete density to water density (concrete density g/cm3) (γ/γw), water-cement ratio (W/C), and sand-cement ratio (S/C) as input variable and the compressive strength (Fc) as the study output. The dimensionless factors have been derived to eliminate data handling complexities and improve model performances. The 230 data entries from foamed concrete mixes were partitioned into 75% and 25% for training and validation data, respectively. At the end of the model execution, it was found that the response surface methodology (RSM) produced a symbolic closed-form equation like the genetic programming (GP), evolutionary polynomial regression (EPR), and the group method of data-handling-neural network (GMDH-NN). Even though the RSM closed with a minimum error, the GP, EPR and GMDH-NN were faster in runtime. The overall outcomes show that the GP outclassed the EPR, RSM and the GMDH-NN, though with minor margin. Meanwhile the EPR produced the highest outliers from the ±25% test of accuracy envelope. Overall, the present models outperformed those reported in the literature due the parameter reduction through dimensionless factors derivation and provided a decisive model to predict the Fc of foamed concrete.

Stress Strain Behaviour of Solid Block Masonry Prism under Axial Compression

Masonry is possibly the primary construction element currently in widespread use throughout the world. Load-bearing masonry building is prevalent in developing countries for home construction. When properly constructed, masonry is frequently a more cost-effective and energy-efficient alternative to reinforced concrete for wall building. In addition to performing the dual roles of supporting weight and enclosing space, structural masonry boasts a high level of fire resistance, thermal and acoustic insulation, and exposure protection. The remarkable durability and low maintenance costs are further evident benefits. Masonry has a significant role in building construction, particularly in structures, as it is regarded as the primary component of the building. The eco-friendly solid block is prepared by adding the following by-products like coal ash, granite powder, olivine sand etc., all these ingredients used for manufacturing the solid block are waste materials from various industries. Thus, extensive testing is necessary to assess their load carrying capacity and secant modulus accurately. Masonry prisms were developed with five-layer solid blocks and tested for their stress-strain characteristics and secant modulus and the test outcomes were compared with conventional fly ash cement blocks. Eco-friendly solid blocks offer a persuasive substitute for ecologically conscious approaches to building by preserving structural integrity and functionality while promoting sustainability.

The Impact of the Location of a Passive Frame House on Its Energy Demand for the Purpose of Heating—A Case Study

The reduction of energy demand in buildings is one of the key challenges in contemporary construction. To this end, the application of structural and material partitioning solutions that provide a high level of thermal insulation and the employment of technical installations with high energy performance have become widespread. However, there are a number of other factors that can reduce energy demand. These include the optimal use of heat gains from solar radiation. An aspect that is often discussed in the literature is the overheating of buildings due to excessive heat gains from solar radiation. This article is a case study showing the impact of the orientation of a single-family passive house on its heating energy demand. The building under consideration is located in Central Europe. External climate parameters measured directly at the site during experimental examinations were used for the calculations. This paper adopts six calculation options, considering the different orientations of the glazed façade. As the simulations showed, the effect of solar radiation on the energy demand between two extreme options of glazing orientation, that is south and north-facing orientation, reached 4.7% of the annual energy demand for heating, while for the option corresponding to the actual location of the building and the option involving south-facing windows, the difference was 0.3%, respectively.

Operation optimization and performance evaluation of a ventilated heating floor in a nearly-zero-energy building with mixed power

With the proportion of renewable energy in the construction sector increasing and the structure of energy systems becoming increasingly complex, it is crucial to optimize the operation strategy of building energy systems with thermal energy storage for improving multi-performance. However, conventional heuristic optimization algorithm exhibits low searching speed and converges slowly, which is hard for operation optimization of such systems. In this study, with a binary particle swarm optimization (BPSO) algorithm coupled with experience-based searching guiding strategy, the operation of a ventilated floor heating system in a nearly-zero-energy building was optimized . System performance under different optimization objectives and combinations, including reducing operation cost and carbon emission fee, meanwhile increasing wind power consumption and thermal comfort time, was investigated. Results show that with the experience-based accelerating strategy, the BPSO algorithm converged fast and found more reasonable solutions. In contrast, multi-objective optimization yielded better and diverse feasible solutions were found than single-objective optimization. By optimizing operating costs, wind power consumption, and environmental costs, the best comprehensive solution was obtained. The cost range of energy consumption and carbon emissions within 10 days is 19.24–22.17 yuan and 17.45–20.11 yuan, respectively. The proportion of thermal comfort time is 95.39–95.82%. However, due to high thermal insulation level, thermal comfort time under different optimization objectives showed little difference.

Evaluating the impact of peat soils and snow schemes on simulated active layer thickness at pan-Arctic permafrost sites

Abstract Permafrost stability is significantly influenced by the thermal buffering effects of snow and active-layer peat soils. In the warm season, peat soils act as a barrier to downward heat transfer mainly due to their low thermal conductivity. In the cold season, the snowpack serves as a thermal insulator, retarding the release of heat from the soil to the atmosphere. Currently, many global land models overestimate permafrost soil temperature and active layer thickness (ALT), partially due to inaccurate representations of soil organic matter (SOM) density profiles and snow thermal insulation. In this study, we evaluated the impacts of SOM and snow schemes on ALT simulations at pan-Arctic permafrost sites using the Energy Exascale Earth System Model (E3SM) land model (ELM). We conducted simulations at the Circumpolar Active Layer Monitoring (CALM) sites across the pan-Arctic domain. We improved ELM-simulated site-level ALT using a knowledge-based hierarchical optimization procedure and examined the effects of precipitation-phase partitioning methods (PPMs), snow compaction schemes, and snow thermal conductivity schemes on simulated snow depth, soil temperature, ALT, and CO2 fluxes. Results showed that the optimized ELM significantly improved agreement with observed ALT (e.g. RMSE decreased from 0.83 m to 0.15 m). Our sensitivity analysis revealed that snow-related schemes significantly impact simulated snow thermal insulation levels, soil temperature, and ALT. For example, one of the commonly used snow thermal conductivity schemes (quadratic Sturm or SturmQua) generally produced warmer soil temperatures and larger ALT compared to the other two tested schemes. The SturmQua scheme also amplified the model’s sensitivity to PPMs and predicted deeper ALTs than the other two snow schemes under both current and future climates. The study highlights the importance of accurately representing snow-related processes and peat soils in land models to enhance permafrost dynamics simulations.

History of Development of Engineering Support of Buildings and Thermal Insulation of Enclosing Structures

The article considers the process of development of the main means of engineering support of buildings – lighting, heating, and ventilation. How over time and the development of science and technology improved ways to create a comfortable environment. The first artificial source of light and heat was the hearth. With the advent of torches and oil lamps, these functions separated and developed in parallel. At the same time, up to the 19th century, both heating (hypocausts, fireplaces, steam and water heating, etc.) and lighting (candles, gas lighting, etc.) were impossible without fire. Ventilation remained natural until the invention of the centrifugal fan in the nineteenth century. In parallel with the issue of heating, the issue of thermal insulation arose. When choosing building materials and structures, their availability in a given region, thermal characteristics and work in a given climate played an important role. The required level of thermal insulation was achieved by increasing the thickness of the wall, the size of the openings and their filling. In the era of the “Enlightenment” (17th – 18th centuries), there is a turning point in the understanding of the world. The “classical” sciences are developing actively and universities and engineering schools are opening. If earlier science and practice existed in parallel, now the inventions of scientists began to be implemented much faster. In the 19th century, electricity appears. This is another important point in the development of engineering. In the 21st century, it has almost completely replaced fire in human life (LEDs, LED, infrared and radiant heat, ventilation and air conditioning systems, etc.). A person no longer depends on nature. If in ancient times people sought to subdue it to himself then in the 21st century, the goal is to live in harmony with nature, which preservation and replenishment of the used resources is the search for environmentally friendly solutions without harm to humans and the environment.

Cooling Demand and Indoor Temperatures of a Detached House in Southern Finland: Feasibility of a Monthly calculation Method

The aim of this study was to compare dynamic thermal modelling with a monthly calculation method based on a European standard and Finnish regulations. Effect of thermal insulation level of a building envelope, solar shading, solar heat gain coefficient and window area on cooling demand were also studied. Increasing the thermal insulation of building shell increased indoor temperatures and hence cooling demand considerably. Solar shading by blinds between window panes decreased indoor temperatures effectively, indicating the performance of passive cooling in Finnish climate. There were rather large differences between calculated indoor temperatures and cooling demands between the two methods although both methods were able to take into account differences between variations in building shell. According to the study, the monthly calculation method underestimates the cooling need which can be significant considering the energy consumption of buildings. Therefore, it is recommended to investigate both summer temperatures and the cooling energy needs of detached houses by modelling.

Inequalities in exposure to indoor environmental hazards across England and Wales – can more energy efficient homes help?

Housing is an important modifier of outdoor environmental hazards due to features such as the amount of passive and active ventilation a dwelling receives, the proportion of the façade that is glazed and the building’s thermal insulation levels. Using Artificial Neural Networks based on an indoor building physics model, we simulate indoor temperature and air pollution concentrations in ~15 million English and Welsh dwellings and assess how exposure to indoor hazards varies for different population groups. The model is derived using simulations from the dynamic thermal modelling tool EnergyPlus, taking a spatially-distributed housing stock as input. Results are linked to the latest 2021 Census data on area-measures of population demographics to assess if vulnerable subgroups bear a disproportionate risk from indoor environmental hazards. We find neighbourhoods in England and Wales with a higher proportion of infants, ethnic minorities and income-deprived populations experience higher two-day maximum indoor temperatures in summertime; whilst more ethnically diverse areas have elevated annual average indoor concentrations of outdoor-sourced PM2.5. Areas with a higher proportion of those aged 65+ had a lower standardised indoor temperature (SIT) in winter, increasing the risk of fuel poverty. We then implement a stock-wide, home energy retrofit, in line with national decarbonisation targets. Results suggest energy-efficient building interventions may exacerbate heat inequalities without the provision of external shading, but improve population exposure to winter indoor temperatures and indoor concentrations of ambient-sourced PM2.5.

Optimal sizing and operation of seasonal ice thermal storage systems

Ice storage systems can be used as an efficient cooling source during summer, as well as a heat source for heat pumps during winter. The non-linear behavior of the heat exchange process in storage makes formulations for optimizing the design and operation of these technologies complex. In this work, we propose a quadratically-constrained mixed-integer programming formulation, that can capture the latent and sensible behavior of the storage and its impact on the delivery of heating and cooling. A building demonstrator integrating an ice storage device was used as a case study. Monitoring data were used to validate the simplified ice storage model employed in the optimization. Results showed that the most common optimal storage cycle requires freezing the water during late winter and when the air temperature falls below 0∘C. Increasing the storage volume increases both storage efficiency and the amount of free cooling available during summer. For these reasons, economies of scale can make larger systems more competitive than smaller ones. Storage size and thermal insulation level affect the duration of the charging and discharging phases. Thermal insulation improves seasonal efficiency and free cooling significantly. A higher CO2 emissions price does not yield significant benefits in terms of emissions reductions. High investment costs and the seasonal variation in CO2 intensity of electricity reduce the economic and environmental competitiveness of long-term ice storage systems, respectively.

A dataset of criteria on the use of thermal insulation solutions in building facades located in Norway, Portugal and Italy.

The building sector is responsible for a significant percentage of the energy consumption in Europe. The level of thermal insulation of the building envelope leads to decrease energy consumption, thus contributing towards a sustainable and efficient built environment. As a result, the choice of the most suitable thermal insulation solution to be applied both in new construction and in retrofitting of building facades is fundamental for a satisfactory thermal performance of the building. Nevertheless, the thermal insulation solution should not be chosen considering only the thermal performance, but rather based on a set of performance parameters (i.e., water resistance, fire performance, impact on the environment and human health, among others) and climate-related requirements. This data article includes a dataset on criteria adopted in three European countries (namely Norway, Portugal, and Italy) considering a PESTE analysis (i.e., criteria related to Political, Economic, Social, Technological, and Environmental questions). The main objective was to evaluate the knowledge and perception of people living and/or working in these countries about the use and the performance of thermal insulation solutions in building facades. To this aim a questionnaire was developed within the scope of the EEA Granted EFFICACY research project (November 2022 - February 2023), whose overall objective is to create a database that serves as a reference for the choice of thermal insulation solutions to be applied in building facades for thermal and energy performances optimization. This database contributes to systemize criteria and can be extended by other researchers or professionals in the area, as well as in other countries.

Dynamic interdependence of comfortable thermal conditions and energy efficiency increase in a nursery school building for heating and cooling period

The paper studies the influence of building function and orientation, level of thermal insulation on energy efficiency and occupant thermal comfort dynamic interdependence. Energy state dynamic modelling of the typical preschool educational facility (Kyiv, Ukraine) was carried out with different levels of thermal comfort in each of the zones, taking into account occupants' activity, metabolism, clothing, etc. The research was conducted for the heating and cooling periods, taking into account the operational peculiarities of the building. Increasing the thermal resistance from the base version to the Swedish norms reduces energy consumption by 32% for the heating period, compared to the base version. The introduction of intermittent heating leads to a reduction of energy consumption by 14%, compared to the base version. Intermittent heating and ventilation and increased thermal protection to Swedish standards can reduce energy consumption by 42%. The investigation of comfort indicators revealed that during the transition period when the heating is turned off, electric heating of the premises is required to maintain the comfort conditions, which increases the heating energy consumption by 18%. Three different options for children's clothing in the summer period to avoid feeling cold were investigated.

Influence of the In-Fill Pattern of the 3D Printed Building Wall on Its Thermal Insulation.

The intensive development of 3D Concrete Printing (3DCP) technology causes constantly increased its share in the construction sector. However, in order to produce products with controlled properties, optimization of the technological process is still required. Automation of production based on additive manufacturing methods streamlines the process by comprehensively manufacturing building components that meet, among others, strength, visual, and insulation requirements. Moreover, the possibility of using computer simulations to assess the properties of the designed elements allows for a multitude of analyzed versions of the constructed partitions, which can be verified at the design stage. Thanks to such an opportunity, the process of designing building elements can be significantly improved. The article presents results related to the assessment of the level of thermal insulation of products that can be produced by additive technology, depending on the applied spatial geometry of the vertical partition and the amount and type of materials used. Eight original solutions of in-fill pattern were designed, for which both Finite Element Method (FEM) computer simulations of thermal conductivity and experimental measurements of thermal conductivity of samples were performed. On the basis of the obtained results, both the correctness of the simulation results for the various analyzed materials and their consistency with the practical results were found. Depending on the investigated geometry, for samples of the same dimensions and using the same material, the differences in the U-factor obtained by FEM analysis amounted to 61%. The best solution from the investigated spatial geometries of the vertical partitions has been indicated. The U parameter in the variant with the best thermal insulation was 0.183 W/m2K, which meets the requirements of Polish construction law. The issues discussed in this work can be the basis for the selection of the best solution possible for practical use during the production of building walls using the 3DCP method fulfilling the guidelines of applicable standards. Furthermore, they can be used as a tool for optimizing geometry in terms of energy savings and reducing waste production by both engineers developing 3DCP technologies and architects using innovative techniques for manufacturing building structures.

EVALUATION OF THE EFFICIENCY OF THE OPTIONS FOR THE MODERNIZATION OF THE HEAT SUPPLY AND THERMAL PROTECTION OF THE OFFICE BUILDING

The concept of implementation of the state policy in the field of ensuring the energy efficiency of buildings in terms of increasing the number of buildings with close to zero energy consumption and the National Plan for the increase in the number of buildings with close to zero energy consumption are aimed at achieving the goals set out in the Energy Performance of Building Directive, which indicates significant steps towards improving the energy efficiency of the Ukrainian construction sector. According to the above regulations, a prerequisite for new construction and renovation of existing buildings is to ensure a high level of thermal insulation of the building and the use of renewable sources to cover energy consumption. The work carried out a feasibility study of the modernization of an office building in the city of Kyiv to the level of a highly energy-efficient building using a heat pump to provide the necessary heat supply. Estimation of generation of required heat supply of the building by the heat pump and used electrical energy by the heat pump is based on the simulation results in the GeoTSOL software environment. In order to assess the economic attractiveness of the project for upgrading an existing building to the level of a highly energy-efficient building using renewable sources for heat supply, the calculation of the energy demand for heating in the Design Builder software environment and the integral costs for heating the building using renewable and traditional energy sources at different levels of thermal protection was made. The results obtained indicate attractive, both from an economic and environmental point of view, the possibilities of implementing the construction of a highly energy-efficient building that uses renewable energy sources for heat supply.

Energy performance gap of the Italian residential building stock: Parametric energy simulations for theoretical deviation assessment from standard conditions

Energy Performance Gap (EPG) is a crucial issue in the building sector that can lead to an overestimation of the national energy policies. It is the difference between the calculated energy consumption and actual energy use, and it is relevant mainly for space heating. As EPG quantification or correction methods could lead to more realistic energy policies, EPG has become a focus of many studies and research. In this framework, this study aims to quantify the theoretical deviation of EPG, i.e., concerning to the standard conditions, for the Italian residential building stock by performing parametric energy simulations of thousands of representative reference buildings. After a comprehensive thermophysical characterization of the national building stock, parametric simulations were carried out by varying the main standard conditions set in the Energy Performance Certificate (EPC) calculation. This approach allowed the quantification of EPG according to the climatic zone, building type, usage profile, and thermal insulation level of buildings, while also analysing the influence of these parameters on the EPG and checking for prebound or rebound effects (i.e. when standard consumption is greater or smaller than actual one). The study identified a range of EPG variability for both prebound (0% to +80%) and rebound (−30% to 0%) effects and quantified an average EPG between −3 and +16 kWh per heating degree day of the selected location as a function of the usage profile. This work represents the first attempt to calculate the EPG of the Italian residential building stock and it could lead to the correction of the national energy policies implemented in the building sector.

In-situ assessment of the thermal performance of earth masonry construction

The interest in traditional earth constructions has grown in Europe since a few years. This growing interest can be attributed to the fact that earth has among other qualities a good capacity for the hygrothermal regulation inside a building. This well-established ability of earth to store and manage heat and moisture has been extensively studied in the past at the material scale. However, the evaluation of the building envelop performance is rarely achieved in practice. This study presents an evaluation of the thermal performance of earth masonry construction based on in-situ measurements under real conditions of exposure. The construction consists of a single unoccupied room with habitable surface area of 12.9 m2 located in Canohès in the Southern France. Firstly, the airtightness of the envelop was quantified with the blower door test. The air permeability results indicated a very good level of airtightness. Then the thermal insulation of the envelop was measured according to the ISABELE method (In Situ Assessment of the Building EnveLope pErformances). The latter is a method developed by the CSTB to deduce the transmission heat transfer coefficient of the building with its uncertainty within short unoccupied period (few days). The results of the different ISABELE tests demonstrated that the total thermal insulation level of the tested envelop could be classified as good to average according to the scale of the building heat loss coefficient (Ubat) of the French Energy Performance Diagnosis. The results of the ISABELE tests were confirmed by the outcomes of a Coheating test conducted during a long period of 3 months. This study gives encouraging results on the application of the ISABELE method on earth masonry buildings to deduce the thermal performance of their envelope quickly, instead of a complete Coheating test which can be too long to apply in practice.

Energy and Environmental Analysis of Renewable Energy Systems Focused on Biomass Technologies for Residential Applications: The Life Cycle Energy Analysis Approach

Sustainability and resilience are major challenges for the building sector in order to meet energy efficiency and low carbon emissions goals. Based on the defined and quantified targets of the EU climate change policy, Renewable Energy Systems (RESs) are among the top-priority measures for accomplishing the target of decarbonization in buildings. Nevertheless, the choice of the type of RES is not a one-dimensional problem, and the optimal combination may not be unique. The aim of this paper is the energy and environmental evaluation of renewable energy technologies with emphasis on biomass and solar thermal systems for heating applications in residential buildings. More specifically, and aiming at the maximum possible contribution of renewable energy sources in the total final energy consumption for the needs of zero energy buildings, different scenarios are presented based on a Life Cycle Energy Analysis (LCEA) approach. The methodology is based on quantifying the environmental impacts (midpoint analysis), as well as endpoint analysis, in order to define the impact on human health, ecosystem damage, and resource depletion. The LCEA has been conducted, supported by the SimaPro tool, ensuring the environmental impact assessment result. A combination of RES technologies based on solar and biomass are examined and compared to conventional fossil fuel heating systems according to technical, energy, and environmental criteria. Finally, the energy system technologies were compared in correlation to a building’s thermal insulation level. The first set of simulations fulfilled the minimum thermal insulation requirements, according to the national energy performance regulation, whilst the second set of simulations was based on increased levels of insulation. The point of this analysis was to correlate the impact of thermal insulation to RES technologies’ contribution. The results determined that the best available energy solution, focusing on technical and environmental criteria, is the combination of biomass and solar thermal systems for covering the heating processes in residential buildings. More specifically, the combined biomass–solar system has a lower overall environmental impact, due to the reduction in gaseous pollutant emissions, as well as the reduction in the amount of used fuel. The reduction in the total environmental impact amounts to a percentage of approximately 43%.

Evaluation of the Impact of Window Parameters on Energy Demand and CO2 Emission Reduction for a Single-Family House

This article deals with the determination of the impact of selected parameters on energy consumption for heating and cooling purposes and CO2 emissions. Mathematical modelling combined with planning a computational experiment was adopted as the research method. The database for creating the models was developed using building energy simulations performed with DesignBuilder software. A single-family house with an area of 101 m2 was the subject of this study. Four deterministic mathematical models for the estimation of annual energy demand for heating, cooling, total final energy demand, and CO2 emissions were developed. Four parameters affecting the energy balance of the house: the area of the glazing system (three levels), U-value of windows (two-, three- and four-pane), U-value of external walls (0.1, 0.15, 0.2 W/m2K) and location (Warsaw, Berlin, Paris) were considered. The article discusses in detail the influence of individual factors on the energy demand and their common interactions. It was found that the level of thermal insulation of the glazing system plays the most important role in saving energy. This factor was the only one to show a stable and significant reduction in house energy demand, and thus a reduction in CO2 emissions for all four objective functions.

The Influence of Addition of Fly Ash from Astana Heat and Power Plants on the Properties of the Polystyrene Concrete

Due to the constant increase in prices for energy resources, as well as the reduction in non-renewable resources in most developed countries of the world, the energy consumption standards of buildings are constantly decreasing, and the requirements for the level of thermal insulation of building envelopes are increasing. The increasing requirements in the level of thermal insulation of enclosing structures make the issues of improving and developing new materials and products become more urgent. Polystyrene concrete has good high-thermal and sound-absorbing properties. This serves as a means of reducing costs, improving thermal insulation, reducing the dead load (weight) on the building and outside, among many other advantages. However, concrete made with polystyrene foam as a substitute for large aggregates has insufficient strength, due to the fact that the cement has low adhesion to the polystyrene foam. Based on the research of scientists and authors on the possibility of using industrial waste, it was assumed that the addition of fly ash to the composition would strengthen the matrix and the degree of compression of the polymers by the cement matrix as a result of the presence of nanoparticles in the fly ash and their positive effect on the structure and properties of the composition. The aim of the study was to develop a heat-insulating polystyrene concrete based on a binder using fly ash and to investigate its physical and technical properties. The properties of fly ash have been studied for the purpose of safe use in mixtures to increase strength properties and improve adhesion to polymers. The involvement of industrial waste from the ashes of coal from Kazakhstani deposits will contribute to the ecological improvement of the environment of the megacities of Kazakhstan. The effect obtained from the optimal combination of the characteristics for a building material is the improved physical and mechanical properties of heat-insulating materials.

Overheating vulnerability assessment of energy retrofit actions in a multi-apartment building in Podgorica, Montenegro

The study aimed to assess the overheating vulnerability of an existing multi-apartment building built in 1971 in Podgorica, Montenegro. The building consists of 80 apartments and is mostly still in its original state. Firstly, the building was modelled in EneryPlus, and a parametric study was performed with jEPlus. The energy need for heating and cooling was simulated using parameters such as thermal insulation level, window properties, external surface solar absorptivity, shading activation set-point, and natural ventilation cooling intensity. Moreover, the energy need was determined for four different climate periods, namely for the current and three future periods up to the end of the 21st century under the RCP8.5 climate change scenario. The total number of building models equalled 648 for each of the four climate scenarios, resulting in 2,592 simulated cases. After that, the overheating vulnerability score was determined using the minimax regret method and cooling energy need as a performance indicator. The best retrofit action was determined by identifying the most favourable combination of the overheating vulnerability and total energy need. The results deliver the appropriate energy retrofit actions to limit the increase in overheating risk and provide for climate change adaptation of the multi-apartment building stock in Montenegro.

PRIVATE HOUSEHOLD HEAT PUMP-BASED HEATING SYSTEM WITH PHOTOVOLTAIC PLANT

Heat supply is the most energy-consuming industry in Ukraine. The reason for this is a large number of buildings built with a low level of thermal insulation, outdated thermal energy equipment and infrastructure, as well as a low level of implementation of heating systems based on renewable energy sources. Heat pumps are one of the alternatives to fossil fuel boilers for use in household heating systems. The problem of optimizing the operation of heating systems based on heat pumps is of practical importance, since its solution will potentially allow achieving several energy effects, including: reducing operating costs, as well as increasing the level of autonomy of the heating system in the case of providing electricity from an autonomous photovoltaic plant. The article presents the results of mathematical modeling of the heating system of a private house based on a heat pump, a thermal energy accumulator and a photovoltaic plant in the MATLAB/SIMULINK software environment. The model was created for the research purpose of the heating system of a private house with renewable energy sources through structural simulation modeling and conducting a comparative analysis of its management methods for three options (methods): "reactive", "economic" and "autonomous". It was found that the average annual operating costs with the "economic" method of management decreased by 22 % compared to the "reactive" method of management. When using the "autonomous" method of control, the annual maintenance cost of the system due to photogeneration increased by 48 %.